I've found out some good information. The stickers/imprints on the windows in the corners give the exact measurements in mm. If anyone with an Aktiv minds checking and either posting the images of the stickers/imprints OR using my attached image to figure out the sizes, it would be awesome!

Thanks for the suggestions of where to find Aktiv owners, I'll try some of those. Cross posting here in case an Aktiv owner sees this first!